Market Anarchism is the doctrine that the legislative, adjudicative, and protective functions unjustly and inefficiently monopolised by the coercive State should be entirely turned over to the voluntary, consensual forces of market society.

As Thomas Paine wrote in The Rights of Man (1792):

Great part of that order which reigns among mankind is not the effect of government. It has its origin in the principles of society and the natural constitution of man. It existed prior to government, and would exist if the formality of government was abolished. The mutual dependence and reciprocal interest which man has upon man, and all the parts of civilised community upon each other, create that great chain of connection which holds it together. The landholder, the farmer, the manufacturer, the merchant, the tradesman, and every occupation, prospers by the aid which each receives from the other, and from the whole. Common interest regulates their concerns, and forms their law; and the laws which common usage ordains, have a greater influence than the laws of government. In fine, society performs for itself almost everything which is ascribed to government.

The first explicit defender of Market Anarchism was the 19th-century economist and social theorist Gustave de Molinari. The idea was taken up by the individualist anarchists, particularly those associated with Benjamin Tucker's journal Liberty. More recently, Market Anarchism has been revived by a number of thinkers in the libertarian movement. The terms "anarcho-capitalism" and "voluntary socialism" have both been associated with the Market Anarchist tradition.